What's special about Active Manuka Honey?

on Sunday, 21 April 2013. Posted in Honey Research

For the past 26 years honey researchers at the University of Waikato have been investigating...

For the past 26 years honey researchers at the University of Waikato have been investigating what many local New Zealanders have accepted as common wisdom: our local manuka honey is a superior treatment for wound infections. Manuka honey is gathered in New Zealand from the manuka bush, Leptospermum scoparium, which grows uncultivated throughout the country.

All honeys have an antibacterial activity, due primarily to hydrogen peroxide formed in a "slow-release" manner by the enzyme glucose oxidase present in honey, which can vary widely in potency. Some honeys are no more antibacterial than sugar, while others can be diluted more than 100-fold and still halt the growth of bacteria. The difference in potency of antibacterial activity found among the different honeys is more than 100-fold.

Manuka honey can contain additional antibacterial components found only in honey produced from Leptospermum species: this unusual antibacterial activity has been known as the Active Factor or "Active Manuka". There is evidence that two or more antibacterial components may have a synergistic action to give this unque activity.

Only some of the honey sold as manuka honey has this Active type of antibacterial activity. This has become known as “Active Manuka Honey”.

The Active Manuka Factor is not affected by the catalase enzyme present in body tissue and serum. This enzyme will break down, to some degree, the hydrogen peroxide which is the major antibacterial factor found in other types of honey. If a honey without the Active Manuka Factor were used to treat an infection, the potency of the honey's antibacterial activity would most likely be reduced because of the action of catalase.

The enzyme that produces hydrogen peroxide in honey is destroyed when honey is exposed to heat and light. But the Active Manuka Factor is stable, so there is no concern about Active Manuka Honey losing its activity in storage.

The enzyme that produces hydrogen peroxide in honeys becomes active only when honey is diluted. But the Active Manuka Factor is active in full strength honey, which will provide a more potent antibacterial action diffusing into the depth of infected tissues.

The enzyme that produces hydrogen peroxide in honeys becomes active only when the acidity of honey is neutralised by body fluids. The enzyme that produces hydrogen peroxide in honeys could be destroyed by the protein-digesting enzymes that are in wound fluids.

The antibacterial activity of the Active Manuka Factor diffuses deeper into skin tissues than does the hydrogen peroxide from other types of honey.

Honey with the Active Manuka Factor is more effective than that with hydrogen peroxide against some types of bacteria. For example, Active Manuka Honey with the Active Manuka Factor is about twice as effective as other honey against Eschericihia coli and Staphylococcus aureus, common causes of infection in wounds. It is much more effective than other honey against Helicobacter pylori, a common cause of peptic ulcers.

The potency of the antibacterial activity in Active Manuka Honey that is due to the Active Manuka Factor is measured by an assay developed by the Honey Research Unit: The killing power of samples of honey tested against the most common wound-infecting species of bacteria, Staphylococcus aureus.

It is compared with that of solutions of a standard antiseptic, phenol (also known as carbolic acid) at various concentrations.

This is done with the enzyme catalase added to the samples of honey so that all hydrogen peroxide is destroyed and thus only the Active Manuka Factor activity is seen.

The Active Manuka Factor activity is then reported as the equivalent concentration of phenol with the same level of antibacterial activity. (For example, a Active Manuka Factor activity rated as 10 will kill Staph. aureus as effectively as will a 10% phenol solution.)

Many medical professionals are using Active Manuka Honey - and getting excellent results in patients with infected wounds that have not responded to any standard treatment such as antibiotics. For most of the various brands of registered medical products based on honey that are sold for wound treatment and ophthalmology the manufacturers have opted to use Active Manuka Honey (with an activity rating ranging from 12 to 30).